[Hammerstein]

Hi all,

This is probably an esoteric question, but does anyone know how to get more information about vintage CDPs that lack a manual? I ask, because my family has an old JVC XL-V311 (1989, I believe) sitting around, and I'm trying to determine what to do with it.

Lacking a really good source for comparison, I'm in no good position to evaluate it, but I'm curious to see its numbers, if possible. If the outside labelling is to be believed, it has dual 18 bit noise-shapening DACs and is a 4 times oversampling unit. That's about all I know. I suppose I could open it up, though, but I'd prefer not to.

Amazingly enough, the unit does work perfectly, and it has an surprisingly powerful line out. On my Gilmore Lite with an AKG K271S, I had to turn the dial a few milimeters from the minimum for it to be at a good listening volume (I nearly blasted my ears off when I hooked it up and didn't turn the volume down first).

Thanks for your time!

 

[memepool]

No idea about that particular model but the best source is going to be old magazines. If you can find something like the Hi-Fi Choice yearbook for that year it will have comparisons of every player on the market at the time.

With respect to the numbers I suspect this belongs to the "bit wars" period.

In brief since the inception of CD in the early 1980s there was a development path with multibit DACs where more bits and more oversampling was marketed as the way towards better sound.

Philips started with 14 bit 4 x oversampling and Sony with 16 bit 2 x oversampling and because the Philips players were initially better recieved 4 x oversampling was used as a marketing tool and 'obviously' 16 bits is better than 14 but not as good as 18 or 20 ...etc...etc.

So by 1989 2 x 18 bit with 4 or 8 x oversampling was pretty standard in Japanese players.

Philips then came back with 1 bit Delta Sigma "bitstream" of course which was much cheaper to make and has been more or less the industry standard ever since.

The fact your machine is still working is probably down to the superior build quality especially in the transport so if it has digital outputs, which it ought to have done by 1989, then it'll make a good transport.

The DACs could well be one of the 18 bit Burr Brown chipsets which were quite common at the time so it's worth lifting the lid to check. These are pretty smooth and very detailed and still quite highly rated in NOS circles.

Overall CD players were an expensive luxury item back then and were made to last so enjoy it while it keeps spinning.

 

[Herandu]

What a find! The 18 bit, 4x oversampling chip they used was far smoother and more accurate than the 19 bit 2x chips that put Yamaha CD players on the map in that era. The sampling works on a sliding scale on the 18 bit chips. So there is a lot more detail in low level sound passages in the 18 bit decoding than in a 16 bit chip. The 4x oversampling also lifted the sampling noise higher than the 44.1KHz of the 16 bit machines. Tops were cleaner for one.
If I remember correctly, it also uses a 3 beam focusing laser pick-up. The fact that yours still plays goes to show that you have one that was spot on with the factory set up.

Knowing what we now know about modifying analogue output stages, I reckon that a proper mod of the oversampling filter and an update of the analogue stage would give you a sound that can stand up to a lot of expensive CD players made today. That sliding scale DAC technology was a victim of cost, even though it was far better sounding than even modern day decoding methods.

 

[sugarinthegourd]

I used to have a Magnavox CDB-650 CD player (Philips-made in Belgium) which at the time was getting a lot of accolades (In Stereo Review ca 1986, Julian Hirsch called its sound "as good as any CD player at any price" (paraphrasing from memory). Unfortunately, I LENT it to a friend who was playerless, and he then decided to GIVE it to another guy who subsequently broke it. Arrgh.

Anyway, I really liked it, and I often wonder how the perceived SQ of this player would have held up over the past 20+ years. It even had SPDIF out, and interestingly, 2 sets of RCA outs, one was "filtered" for a "warmer" sound. Not sure what the filtering was, but these outputs did have a slightly warmer, more analog sound.

 

[Hammerstein]

Very interesting stuff

Unfortunately, there's no digital out on this one (bleh). Just analog out. One of the reasons it still works is because it probably doesn't have 100 hours on it yet, though. It's my father's, and he got it as a gift but never really used it.

Given that it doesn't have a digital out, I'm going to guess it's probably not worth much all-in-all except as an extra player for an inexpensive setup someplace?

 

[memepool]

Quote:

Originally Posted by Hammerstein /img/forum/go_quote.gif Very interesting stuff Given that it doesn't have a digital out, I'm going to guess it's probably not worth much all-in-all except as an extra player for an inexpensive setup someplace?

On the whole I find multibit DAC's are more involving to listen to than the modern DS ones personally, as these can sound a bit airbrushed.
The only similar rig I have is the Sony DZ-555 PCDP which is lovely but it depends entirely on how well JVC designed the player as a whole.

Theway to be sure is plug it in next to a more modern machine and compare them. You may be pleasantly surprised

 

[Herandu]

Quote:

Originally Posted by memepool /img/forum/go_quote.gif On the whole I find multibit DAC's are more involving to listen to than the modern DS ones personally, as these can sound a bit airbrushed.

I would 2nd that. The modern chip sets spread the analogue output evenly, no matter if it is a quiet or loud passage. The old multi-bit DAC chip sets like the one that Yamaha used produced a greater resolution on quiet passages. Guital and piano notes are the type of instruments that sounded far more realistic on the old chip sets such as the 18bit ones.

Modern day DS are able to produce exceptional results, but I feel that the DAC chip sets with balanced current outputs are not as good as the standard output Voltage types. It could be that the current to voltage conversion process is not quite right in some designs. Who knows.

 

[memepool]

Quote:

Originally Posted by Herandu /img/forum/go_quote.gif Modern day DS are able to produce exceptional results, but I feel that the DAC chip sets with balanced current outputs are not as good as the standard output Voltage types. It could be that the current to voltage conversion process is not quite right in some designs. Who knows.

Interesting. I read an interview with Ken Ishiwata of Marantz ,who says he prefered the older BMOS chips to newer CMOS as they used higher voltages to be used which he felt was better for audio usage,

 

[Herandu]

Quote:

Originally Posted by memepool /img/forum/go_quote.gif Interesting. I read an interview with Ken Ishiwata of Marantz ,who says he prefered the older BMOS chips to newer CMOS as they used higher voltages to be used which he felt was better for audio usage,

I picked up on that higher voltage syndrome years ago whilst fixing a Pioneer SX-1250 receiver from a customer. I always found it strange that transistors and ICs running off higher voltage rails sounded far better than lower voltage rails. Only after I did an experiment with a NE5532 and looked at the data sheet did I also notice that even the chip manufacturers seem to know this. The NE5532 runs far smoother and produces a far better performance when powered by a +/- supply of 18V or more.

 

[Hammerstein]

Just thought I'd post an update.

I finally got around to opening the old JVC, and it appears to have (of all things) Yamaha DACs. YM3815 to be specific. I can't find any significant information about these on the net, though. If anyone could tell me anything about them, I'd be appreciative.

If it would be helpful, I can post some pictures.

The power supply is clearly very small, and I can't easily find a label on the transport mechanism. It's mostly plastic, though, so I'm suspecting this was a cheaper model.

There is a spot on the PCB for a digital out, but that area is not populated. It seems that only a more expensive model must've had the digital out.

 

[LarryK2]

I just bought a Denon CDP from 1992 with an 18 bit, 4x oversampling chip. It easily beats several $1K - $2K+ players I auditioned before buying it. I don't know if your CDP has the same chip, but if it does, it's a winner.